In recent years, vehicle seats such as those for automobiles are fitted with various mechanisms and devices for selectively changing the configuration of the seat in various different ways. For instance, a seat back is pivotally attached to a high level part of the floor, and a seat cushion is pivotally attached to the seat back so as to be selectively tilted upward. With the seat cushion kept tilted up onto the seat back, the seat back may be tilted forward (toward the seat cushion).
In such a seat that can selectively change the configuration, the seat cushion can be fixed in the tip up position where the seat cushion is raised to the uppermost position so that the process of stowing the luggage in the created space may be simplified. However, to put the forwardly tilted seat back back to the use position, an operation to release the lock of the tip up lock mechanism is required. To overcome this problem, it is known to provide a lock release mechanism that automatically disables the lock by the tip up lock mechanism when the seat back is tilted forward. See Patent Document 1.
This lock release mechanism consists of a release cam pivotally attached to the cushion frame so as to be rotatable in the direction to engage the lock plate of the tip up lock mechanism and a lock release cable for rotating the release cam. The lock release cable includes a cable and an outer tube encasing the cable. One end of the cable is connected to the release cam, and the corresponding end of the outer tube is fixed to a part of the cushion frame adjoining the release cam. The other end of the cable is connected to a floor hinge that pivotally supports the seat back on the floor, and the corresponding end of the outer tube is fixed to a fixing member attached to an outer side of the lower back (back hinge) of the seat back frame. Thereby, when the seat back is tilted forward, the length of the cable extending between the floor hinge and the fixing part increases on the other end side of the cable so that the cable is pulled on the one end side thereof to rotate the release cam, thereby restricting the rotation (the locking action) of the lock plate.